Recovery of silver metal and electric power generation using a microbial fuel cell

AbstractThe purpose of this study was to model recovering silver metal from wastewater using a two-chambered silver (I) microbial fuel cell (Ag(I)-MFC) with carbon felt electrodes. Both anode and cathode chambers held a volume of about 900 mL. The anode and cathode were graphite felts with a surface area of 122.3 and 34.6 cm2. The chambers were separated by an anion exchange membrane with a surface area of about 78.3 cm2. The MFC was discharged by connecting a 1,000 Ω load resistor. The anode chamber contained 10 mM sodium acetate with 4-(2-hydroxyethyl)-1-piperazine-ethanesulfonic acid buffer medium as electron donors, and the cathode chamber contained synthetic wastewater with silver nitrate. It was verified that the Ag(I)-MFC system in the present study could successfully be operated. The effluent silver concentration was in the range of 0.003–0.153 ppm, representing that the recovery efficiencies for silver ion were in the range of 98.2–92.3% for the Ag(I) concentration range from 50 to 4000 ppm after...